基于模糊阈值的自适应图像分割方法

针对现有的图像分割中自适应分割方法的研究难点,以及传统的模糊阈值分割法中存在窗宽不能自动获取的问题,在确定隶属函数的前提下,以图像的直方图为依据,利用分段计算和反变换的方法,提出了一种自适应模糊阈值的图像分割方法,并将该方法应用于机场目标的分割;该方法实现其窗口宽度的自适应选取,并且有效改善了模糊阈值法对直方图呈不明显双峰的图像分割困难的缺点,拓展了模糊阈值图像分割方法的适用范围,改善了模糊阈值分割方法的分割效果;实验结果表明,该方法对直方图呈单峰和多峰分布的的图像有较好的分割效果和效率。     

基于二维阈值化与FCM相混合的图象快速分割方法

提出了一种将快速二维阈值化与模糊聚类相混合的图象分割方法，以进一步减少快速二维阈值分割中的噪声与错误分割。实验结果表明，利用这种方法分割信噪比较低的图象，能够在很短的时间内得到较为令人满意的分割结果。此外，本文还讨论了这一方法中隶属度函数的选取对分割结果的影响     

遥感图像中复杂海面背景下的海上舰船检测

针对遥感图像中复杂海面背景下海上舰船的检测问题展开讨论,在Itti视觉显著度模型的基础之上进行改进,提出一种基于特征显著度图的复杂海面上舰船的自动检测方法,解决了传统的阈值分割方法在遥感图像复杂海面背景下较难将目标与背景分离的问题.在多种不同复杂海面背景下的舰船检测实验中,与传统阈值分割方法比较,本文方法有较高的检测率和较低的虚警率.     

基于自适应模糊阈值的植物黑腐病叶片病斑的分割

为了更好地研究植物黑腐病,对植物黑腐病病斑图像进行了分割研究,即根据病斑图像的特点,用图像模糊阈值分割法来分割病斑。针对目前图像模糊阈值分割法存在窗口宽度自动选取困难的问题,首先在预先给定隶属函数和图像像素类别数的情况下,提出了图像模糊阈值分割法的自适应窗宽选取方法;然后,针对用图像模糊阈值分割方法难于分割直方图具有单峰或双峰差别很大的图像的问题,提出了一种直方图变换方法,用来对直方图进行变换;最后根据变换后的直方图,再利用自适应模糊阈值分割法对植物黑腐病病斑图像进行分割。用采集到的病斑叶片进行的病斑分割实验结果表明,该算法是有效的与鲁棒的。     

基于组合优化算法的图像阈值分割

针对广义模糊熵图像阈值分割中参数的选取问题,采用两种算法实现自适应选取参数的广义模糊图像熵阈值分割。其中,算法二依据均匀性测度,通过遗传优化算法对参数m在(0,1)区间进行全局寻优,并以广义模糊熵为目标函数,通过粒子群优化算法,对S型隶属度函数中的参数进行全局组合寻优,从而实现广义模糊熵图像阈值分割方法的自动阈值选取。实验结果表明了算法二的有效性。     

应用模糊增强及均值漂移实现红外目标分割

针对复杂环境下红外图像信噪比和对比度低,边缘模糊,目标分割困难的情况,提出一种基于模糊增强和均值漂移图像滤波的红外目标分割方法。首先定义新的隶属度函数,运用模糊集理论进行红外图像增强,避免了传统模糊增强算法的弊病,有效提高目标与背景的对比度;之后利用ICI（交叉置信区）规则确定均值漂移的带宽参数,提出一种新的自适应带宽均值漂移图像滤波方法,实现图像的进一步平滑和聚类;最后利用自适应阈值实现红外目标分割。实验结果表明,算法能够正确有效地分割出复杂环境下的红外目标,并且很好地保持了目标的轮廓细节。     

模糊Renyi熵与QGA结合的快速图像分割

针对非模糊熵的阈值分割方法不能较好地反映数字图像本质上具有的模糊特性,提出一种新的基于模糊熵的图像阈值分割方法。通过模糊隶属度函数将图像直方图信息转换到模糊域,利用模糊Renyi熵计算目标与背景的信息熵。根据最大熵原理,引入量子遗传算法对隶属度函数参数进行寻优,进而得到图像的最佳分割阈值。与典型的阈值法进行对比实验,表明该方法能获得更好的分割结果,满足实时性需求。     

图像的自适应模糊阈值分割法

针对目前图像模糊阈值分割法所存在的窗口宽度自动选取困难的问题,在预先给定隶 属函数和图像像素类别数的情况下,提出了图像模糊阈值分割法的自适应窗宽选取方法.同时, 针对用模糊阈值方法难于分割的具有单峰或双峰差别很大的直方图的图像,提出了一种直方图 变换方法,对变换后的直方图,利用自适应模糊阈值分割法可以获取有效的分割.最后,算例表 明了文中所提方法的简洁性、有效性和很好的鲁棒性.     

基于微粒群和最大模糊熵的图像分割

提出了一种基于微粒群和最大模糊熵的图像分割方法.将图像分为目标和背景,并分别建立相应的模糊隶属函数来描述图像各个灰度级属于目标和背景的模糊特性,进而给出图像模糊熵的描述.在此基础上,根据最大模糊熵准则采用微粒群算法搜索模糊参数的最优组合,确定区分目标和背景的最佳阈值.为了验证方法的有效性,对比进行了图像分割实验,并与双峰法、迭代法和最大类间方差法进行了比较,实验结果表明,效果良好,能够自动、有效地选取阈值,分割效果优于其它三种算法,具有很好的鲁棒性和自适应性.     

广义模糊熵图像阈值分割参数选取的ADE方法

针对广义模糊熵图像阈值分割参数不能自动选取,提出自适应差分进化（Adaptive Differential Evolution,ADE）的广义模糊熵图像阈值分割方法。利用自适应差分进化算法作为优化工具来选取广义模糊熵阈值分割所需要的最佳参数,引入自适应变异算子和提出交叉概率自适应函数对优化过程进行控制,通过把参数带入广义模糊熵的补函数得到图像的阈值,进而得到图像最优分割。为验证其有效性与可行性,分别同基本图像质量评价准则的模糊熵图像阈值分割算法和粒子群优化广义模糊熵图像阈值分割算法相比较,实验表明,针对不同细节的图片,该算法所得分割结果多数情况下背景信息更少,目标信息更清晰,用时更短,分割更稳定且效果良好。     

Chest X-ray enhancement to interpret pneumonia malformation based on fuzzy soft set and Dempster–Shafer theory of evidence

Image enhancement algorithms are commonly used to increase the contrast and visual quality of low-dose x-ray images. This paper proposes an automated enhancement method using soft fuzzy sets with a new decision-making scheme based on Dempster-Shafer theory of evidence for the visual interpretation of pneumonia malformation in low-dose x-ray images, called as XEFSDS. The XEFSDS model first generates an original source x-ray image into a complementary image, then each original and complement image is applied to the characterized image object and background areas of fuzzy space. The S-function is utilized to define fuzzy soft sets for the classification of gray level ambiguity in both images, and hence a decision criterion via Dempster-Shafer approach and fuzzy interval has been adapted to discriminate uncertainties on the pixel intensity and the spatial information. Modified membership grade operations have been performed on each object/background area, and Werner’s AND/OR operator (an aggregation operator) has been utilized to build a new membership function from two modified membership functions. Finally, an enhanced image is obtained from the new membership function via defuzzification. Experiments on different pneumonia X-ray images demonstrate that the XEFSDS scheme produces better results than the existing methods. To show the advantages of the XEFSDS scheme, we have executed a segmentation based examination on enhanced image for the detection of pneumonia malformation as well as abnormal lobe (lobar pneumonia) or bronchopneumonia.     

Image segmentation based on histogram analysis utilizing the cloud model

Both the cloud model and type-2 fuzzy sets deal with the uncertainty of membership which traditional type-1 fuzzy sets do not consider. Type-2 fuzzy sets consider the fuzziness of the membership degrees. The cloud model considers fuzziness, randomness, and the association between them. Based on the cloud model, the paper proposes an image segmentation approach which considers the fuzziness and randomness in histogram analysis. For the proposed method, first, the image histogram is generated. Second, the histogram is transformed into discrete concepts expressed by cloud models. Finally, the image is segmented into corresponding regions based on these cloud models. Segmentation experiments by images with bimodal and multimodal histograms are used to compare the proposed method with some related segmentation methods, including Otsu threshold, type-2 fuzzy threshold, fuzzy C-means clustering, and Gaussian mixture models. The comparison experiments validate the proposed method.     

线阵相机的目标探测性能分析

从线阵相机的背景照度、目标照度和目标与背景的对比度等三个方面分析线阵相机的探测能力.通过仿真与理论分析,得出目标长度、扫描速率、像距、物距对极限探测速度有影响,并且目标长度、扫描速率、像距、目标速度对极限探测距离有影响.     

Fuzzy membership function based neural networks with applicationsto the visual servoing of robot manipulators

It is shown that there exists a nonlinear mapping which transforms image features and their changes to the desired camera motion without measuring of the relative distance between the camera and the object. This nonlinear mapping can eliminate several difficulties occurring in computing the inverse of the feature Jacobian as in the usual feature-based visual feedback control methods. Instead of analytically deriving the closed form of this mapping, a fuzzy membership function (FMF) based neural network incorporating a fuzzy-neural interpolating network is proposed to approximate the nonlinear mapping, where the structure of the FMF network is similar to that of radial basis function neural network which is known to be very effective in the function approximation. Several FMF networks are trained to be capable of tracking a moving object in the whole workspace along the line of sight. For an effective implementation of the proposed FMF network, an image feature selection process is investigated, and the required fuzzy membership functions are designed. Finally, several numerical examples are presented to show the validity of the proposed visual servoing method     

暗环境下利用改良聚光灯测距的方法

针对传统的基于激光和传感器测距方式复杂和昂贵的缺点,提出了一种利用改良聚光灯的测距方法。该方法根据暗环境的特点,使用透镜改良聚光灯产生边缘效果好的光斑;变化的阈值实现对图像中的区域分割,利用环形质心接近的方法确定白光照射的焦点位置,利用三角方法实现测距。经实验验证,该方法区别于使用激光等测距,可以快速地处理复杂背景下的精度要求不高的测距任务,还可以为摄像头提供光源来获取颜色、细节等图像信息。     

Novel fuzzy active contour model with kernel metric for image segmentation

In this paper, a novel region-based fuzzy active contour model with kernel metric is proposed for a robust and stable image segmentation. This model can detect the boundaries precisely and work well with images in the presence of noise, outliers and low contrast. It segments an image into two regions – the object and the background by the minimization of a predefined energy function. Due to the kernel metric incorporated in the energy and the fuzziness of the energy, the active contour evolves very stably without the reinitialization for the level set function during the evolution. Here the fuzziness provides the model with a strong ability to reject local minima and the kernel metric is employed to construct a nonlinear version of energy function based on a level set framework. This new fuzzy and nonlinear version of energy function makes the updating of region centers more robust against the noise and outliers in an image. Theoretical analysis and experimental results show that the proposed model achieves a much better balance between accuracy and efficiency compared with other active contour models.     

A fast recursive algorithm based on fuzzy 2-partition entropy approach for threshold selection

The fuzzy c-partition entropy approach for threshold selection is an effective approach for image segmentation. The approach models the image with a fuzzy c-partition, which is obtained using parameterized membership functions. The ideal threshold is determined by searching an optimal parameter combination of the membership functions such that the entropy of the fuzzy c-partition is maximized. It involves large computation when the number of parameters needed to determine the membership function increases. In this paper, a recursive algorithm is proposed for fuzzy 2-partition entropy method, where the membership function is selected as S-function and Z-function with three parameters. The proposed recursive algorithm eliminates many repeated computations, thereby reducing the computation complexity significantly. The proposed method is tested using several real images, and its processing time is compared with those of basic exhaustive algorithm, genetic algorithm (GA), particle swarm optimization (PSO), ant colony optimization (ACO) and simulated annealing (SA). Experimental results show that the proposed method is more effective than basic exhaustive search algorithm, GA, PSO, ACO and SA.